The field of the disclosure relates generally to wind turbine towers and more particularly, to a composite wind turbine tower and a method for fabricating same.
Known wind turbines include a rotor that includes multiple blades. The rotor is mounted within a housing or nacelle that is positioned on top of a truss or tubular tower. The rotor blades transform wind energy into a rotational force or torque that drives one or more generators that are generally, but not always, rotationally coupled to the rotor through a gearbox. In instances where a gearbox is used, the gearbox steps up the inherently low rotational speed of the turbine rotor for the generator to enable the mechanical energy to be efficiently converted to electrical energy. In other instances, low speed generators are used to generate power without the use of a gearbox.
To increase wind turbine power production and reduce the cost of energy, at least some known wind turbines use large-sized blades (e.g., 50 meters or more in length). The larger blade size results in an increased turbine power rating and more efficient energy production. The larger blades require a supporting tower having a corresponding increased height and size. However, the production of larger wind turbine towers is limited by the horizontal dimension at the base of the tower, the need for a thicker (heavier) plate, and increased manufacturing costs. Currently, most known turbine towers are welded tubular plate steel structures. Such plate steel structures typically use large amounts of steel, which increase material costs. Additionally, large tubular towers require special manufacturing equipment, and may be cumbersome and difficult to transport from the site of manufacture to the turbine assembly site.